- From: Daniela Florescu <danielaf@bea.com>
- Date: Wed, 25 Feb 2004 08:52:02 -0800
- To: Norman Walsh <Norman.Walsh@Sun.COM>
- Cc: public-qt-comments@w3.org
Yes, it does. thank you. Dana On Feb 25, 2004, at 7:55 AM, Norman Walsh wrote: > / Daniela Florescu <danielaf@bea.com> was heard to say: > | Data model: editorial, minor > | > | section 2.2. mentions parent as an example of partial function. > | That's a wrong use of the mathematical concept of partial function. > | A partial function is undefined on a subset of the domain (and > | expected to raise > | errors on this subset), while the parent function does return values > on > | all the nodes. It is true that sometimes the result is the empty > | sequence, but this > | doesn't make it a partial function. > > I don't think the phrase "partial function" actually adds any value to > the explanation. I've reworded it as follows: > > <p>There are some functions in the data model that return the empty > sequence > to indicate that no value was available. > We use the occurrence indicators <emph>?</emph> or > <emph>*</emph> when specifying the return type of such functions. > For example, a node may have one parent node or no parent. > If the node argument has a parent, the > <function>parent</function> accessor returns a singleton sequence. If > the node > argument does not have a parent, it returns the empty sequence. > The signature of <function>parent</function> specifies that it returns > an empty sequence or a sequence containing one node:</p> > > Please let me know if this satisfies your concern. > > Be seeing you, > norm > > -- > Norman.Walsh@Sun.COM / XML Standards Architect / Sun Microsystems, Inc. > NOTICE: This email message is for the sole use of the intended > recipient(s) and may contain confidential and privileged information. > Any unauthorized review, use, disclosure or distribution is prohibited. > If you are not the intended recipient, please contact the sender by > reply email and destroy all copies of the original message.
Received on Wednesday, 25 February 2004 11:51:59 UTC